Evaporator for ice machines



June 27, 1967 P. D. CAMPBELL EVAPORATOR FOR ICE MACHINES Original FiledDec. 13, 1965 MM ZZM M/ United States Patent 3,327,494 EVAPORATOR FORICE MACHINES Paul D. Campbell, P.0. Box 535, Longview, Tex. 75601Continuation of application Ser. No. 513,907, Dec. 13, 1965. Thisapplication Dec. 5, 1966, Ser. No. 599,118 4 Claims. (Cl. 62352) This isa continuation of my copending application Ser. No. 513,907, filed Dec.13, 1965, now abandoned. My invention relates to ice manufacturingmachines in general, and in particular to improvements in column typeevaporators for such machines.

Following is a disclosure of an evaporator for use in the manufacture ofice. This evaporator is of the column type having inner and outertubular members that form an evaporator chamber. Water is sprayed ontothe interior and exterior exposed surfaces of the tubular members andthe temperature reduced to form ice. A refrigerant line extends throughthe evaporator chamber, and expansion of the refrigerant within thechamber effects the above temperature reduction during a freezing cycle.A hot gas line also extends through the evaporator chamber to raise thetemperature of the tubular members dur ing an ice harvest cycle. A hotgas deflection element is utilized on the end of the hot gas line todirect the flow of the hot gas against opposite sides of a discharge endportion of the refrigerant line to limit the build-up of ice in thisregion of the evaporator during the ice manufacturing cycle.

Previously, methods and apparatus have been developed for harvesting icefrom column type evaporators in which a gas such as Freon is utilized asa refrigerant. The gas, after passing through a heat exchanger andcompressor, enters a chamber or void between two concentric tubularmembers or pipes. This chamber is sealed at both ends, thus forcing therefrigerant gas to enter or exit the chamber only at the two designatedlocations. Simultaneously as the gas is discharged into the chamber andwhile expanding therein, water is introduced to the inner and outerexposed'surfaces of the concentric tubular members and transformed intoice due to the heat absorption from the concentric tubular membersoccasioned by the expansion of the refrigerant gas. After the water istransformed into ice, the gas that has become a non-refrigerant throughheat absorption is recirculated between the tubular members. This warmsthe surfaces of the tubular members and eventually enables the ice to beremoved therefrom.

One disadvantage of previously known evaporators of the vertical columntype is that their tubular members tend to cool excessively at theregions nearest the discharge of the refrigerant from the cold gas orrefrigerant inlet. A relatively widespread temperature differential mayoccur on the surfaces of the tubular members, causing the formation ofuneven ice thicknesses during the freezing cycle. Consequently, the icebecomes difficult to remove from the evaporator and produces somethingless than completely satisfactory results.

It is accordingly the general object of my invention to provide animproved column type evaporator for ice manufacturing machines.

Another object of my invention is to improve the ice harvest cycle in anice manufacturing machine having a column type evaporator by utilizationof the discharge of hot gas on the discharge end of the refrigerant lineto facilitate formation of uniform ice thickness on the inner and outertubular members of the evaporator.

These and other objects are elfected by my invention as will be apparentfrom the following description taken in accordance with the accompanyingdrawing, forming a part of this application, in which:

FIG. 1 is an elevation view of a column evaporator embodying theprinciples of my invention;

FIG. 2 is a plan view as seen from above the evaporator shown in FIG. 1;

FIG. 3 is a cross-sectional view of the evaporator of FIGS. 1 and 2 asseen looking along the lines III-III of FIG. 4; and

FIG. 4 is a longitudinal section view of the evaporator of FIGS. 1, 2,and 3 as seen looking along the lines IVIV of FIG. 2.

The numeral 1 in the drawing designates an outer tubular member havingan outer surface upon which ice is formed as will be explainedsubsequently, while the numeral 2 designates an inner tubular memberdisposed inside and being substantially co-extensive with the outertubular member to define an elongated and sealed annular evaporatorchamber 2' therebetween. Ice forms on the innermost surface of innertubular member 1 as will become apparent hereinafter. A plurality ofsupport studs 3 extend from the top of the evaporator for supporting itin a vertical position. A cold gas or refrigerant line 4 extends throughthe evaporator chamber between the inner and outer tubular members,having its discharge end portion 4 terminating in a lower region thereofas shown in FIG. 4. A hot gas line 5 also extends through the evaporatorchamber, with its end portion 5' terminating at a region of the chamberadjacent the discharge end 4 of the refrigerant line 4. A gas outlet 6is provided to enable recycling of the gas through the refrigerationsystem.

An exterior spray ring 7 having a multiplicity of inwardly directedspray nozzles 7' is provided to occasionally discharge water onto theexterior surface of the outer tubular member 1. Similarly, a spray head10 having a plurality of outwardly directed spray nozzles 10 is providedon the interior of the inner tubular member 2 to enable the occasionaldischarge of water onto the interior surface of the inner tubular member2. Water is fed into spray ring 7 through the spray ring connection 8and into the spray head 10 through the conduit 9 which has its upper endextending over the upper surface of the inner and outer tubular memberssealed by the use of a closure strip 11 to which is secured the supportstuds 3 and through which extend hot gas outlet 6, the hot gas inlet 5,and the cold gas inlet 4. Water is supplied to the ring connection 8 andto the conduit 9 through a reducing T 13 and a water header 12.

Disposed on the free end portion of the hot gas inlet 5 is a gasdeflection element 15 which is utilized to direct the flow of hot gasagainst opposite sides of the discharge end portion 4 of the cold gas orrefrigerant line 4. In this instance (see FIGS. 3 and 4) the gasdeflection element is an annular ring having a section removed therefromto define two substantially opposing ends 15' that discharge hot gasagainst opposite sides of the discharge end portion 4' of therefrigerant line 4.

A closure strip 16 is provided at the lower end of the inner and outertubular members 1 and 2 as a convenient means to complete the formationof the above mentioned sealed evaporator chamber. The annular ring 15 issecured to the hot gas line 5 preferably by means of a T 17 which isdisposed on end portion 5 and intermediate the opposing ends 15' of theannular ring 15. Thus, hot gas may fiow freely from the opposing ends15' y of the annular ring 15 toward the discharge end 4' of therefrigerant line 4.

During the freezing cycle, a refrigerant or cold gas such as Freon afterinitially being compressed, is introduced into the evaporator chamber bymeans of the cold gas inlet 4. As the cold gas exits from the dischargeend 4' of the cold gas inlet it expands into the evaporator chamber witha resulting reduction of temperature that cools both the inner and outertubular members 1 and 2. Simultaneously and preferably by automaticmeans such as solenoid valves (not shown), water is sprayed onto theexterior surface of outer tubular member 1 by means of spray ring 7, andon the inner tubular member 2 by means of spray head 10. Since the sprayring and the spray head are disposed at the upper end of theirrespective tubular members, water flows down the tubular members and istransformed into ice while the members are cooled by the expansion ofthe refrigerant passing through the evaporator chamber.

After ice has formed to a predetermined thickness, the flow of coldrefrigerant and the flow of water is stopped by the above mentionedsolenoid valves while a third solenoid valve (not shown) opens to enablehot gas to enter the evaporator chamber through the hot gas inlet 5 forinitiating the ice harvest cycle. Preferably, this hot gas is the Freonwhich was used as the refrigerant gas during the freezing cycle butwhich became warmed during its expansion through the evaporator chamber.Thus, the hot gas may be obtained from a location ahead of the heatexchanger (not shown) in the refrigeration system and is distributedthrough the hot gas inlet to the gas deflection means 15 formed on thelower end thereof. The flow of hot gas upwardly through the evaporatorchamber and ultimately through the hot gas outlet 6 raises thetemperature of the inner and outer tubular members, ultimately causingthe ice to slip therefrom.

It should be apparent from the foregoing that I have provided aninvention having significant advantages. The utilization of a columntype evaporator in the manufacturing of ice is advantageous in that theice harvest time can be significantly decreased. Whereas in previoussuch apparatus ice has tended to form unevenly along the surfaces of theinner and outer tubular members due to rapid expansion of therefrigerant as it leaves the discharge end of the cold gas inlet 4, itis now possible to obtain much more uniform ice thickness throughout thelength. of the evaporator. It is preferable that the ice have a uniformthickness of approximately one-quarter inch throughout the evaporatorlength, and the use of the gas deflection means to distribute the hotgas on discharge end of the cold gas or refrigerant inlet enables theice to form more uniformly in about this thickness.

While I have shown my invention in only one of its forms it should beapparent to those skilled in the art that it is not so limited but issusceptible to various changes and modifications without departing fromthe spirit thereof.

I claim:

1. A vertical column evaporator for ice manufacturing machines, saidevaporator comprising: an outer tubular member; an inner tubular memberdisposed inside said outer tubular member and being substantiallycoextensive therewith to define an elongated and sealed annularevaporator chamber therebetween; a refrigerant line extending throughsaid evaporator chamber, with a discharge end portion terminating in alower region thereof; a hot gas line also extending through saidevaporator chamber, with its end portion terminating at the region ofsaid chamber adjacent said discharge end of said refrigerant line; andgas deflection means carried by said hot gas line to direct the flow ofhot gas against opposite sides of the discharge end portion of saidrefrigerant line to prevent excessive buildup ofice in this regionduring ice manufacturing cycles.

2. The evaporator defined by claim 1 wherein said deflection meanscomprises: an annular ring disposed on the end portion of said hot gasline, with a section removed therefrom to define two substantiallyopposing ends to discharge hot gas against opposite sides of thedischarge end portion of said refrigerant line.

3. In a vertical column evaporator for ice manufacturing machineswherein said evaporator includes an outer tubular member and an innertubular member disposed inside said outer tubular member to besubstantially coextensive therewith to define an elongated and sealedan- I nular evaporator chamber therebetween, the improvement whichcomprises: through said evaporator chamber with a discharge end portionterminating in a lower region thereof; a hot gas line also extendingthrough said evaporator chamber with its end portion terminating at theregion of said chamber adjacent said discharge end of said refrigerantline; and a gas deflection element carried by said hot gas line todirect the flow of hot gas against opposite sides of the discharge endportion of said refrigerant line to prevent excessive buildup of ice inthis region during ice manufacturing cycles.

4. The evaporator defined by claim 3 wherein said deflection elementcomprises: an annular ring disposed on the end portion of said hot gasline, with a section removed therefrom to define two substantiallyopposing ends to discharge hot gas against opposite sides of thedischarge end portion of said refrigerant line.

References Cited UNITED STATES PATENTS 1,866,192 7/1932 Comer 62-298 X3,034,310 5/1962 Lowe 62-352 X 3,053,058 9/1962 Kocher 62352 X 3,146,6109/1964 Lowe 62352 X LLOYD L. KING, Primary Examiner.

a refrigerant line extending-

1. A VERTICAL COLUMN EVAPORATOR FOR ICE MANUFACTURING MACHINES, SAIDEVAPORATOR COMPRISING: AN OUTER TUBULAR MEMBER; AN INNER TUBULAR MEMBERDISPOSED INSIDE SAID OUTER TUBULAR MEMBER AND BEING SUBSTANTIALLYCOEXTENSIVE THEREWITH TO DEFINE AN ELONGATED AND SEALED ANNULAREVAPORATOR CHAMBER THEREBETWEEN; A REFRIGERANT LINE EXTENDING THROUGHSAID EVAPORATOR CHAMBER, WITH A DISCHARGE END PORTION TERMINATING IN ALOWER REGION THEREOF; A HOT GAS LINE ALSO EXTENDING THROUGH SAIDEVAPORATOR CHAMBER, WITH ITS END PORTION TERMINATING AT THE REGION OFSAID CHAMBER ADJACENT SAID DISCHARGE END OF SAID REFRIGERANT LINE; ANDGAS DEFLECTION MEANS CARRIED BY SAID HOT GAS LINE TO DIRECT THE FLOW OFHOT GAS AGAINST OPPOSITE SIDES OF THE DISCHARGE END PORTION OF SAIDREFRIGERANT LINE TO PREVENT EXCESSIVE BUILDUP OF ICE IN THIS REGIONDURING ICE MANUFACTURING CYCLES.